Browse
Submit Data
Databases
API
Help

Dataset Information

25 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Visible light-promoted alkylation of imines using potassium organotrifluoroborates.

ABSTRACT: A mild, redox-neutral, alkylation of imines with potassium alkyltrifluoroborates is described. The reaction proceeds under photoredox conditions at ?30 °C with primary, secondary, and tertiary alkyltrifluoroborates, leading to alkylation products in moderate to good yield in most cases. Aryl-, vinyl-, and cyclopropyltrifluoroborates failed to react under the reported conditions.

SUBMITTER: Plasko DP

PROVIDER: S-EPMC6498442 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Visible light-promoted alkylation of imines using potassium organotrifluoroborates.

Plasko Davis P DP Jordan Christopher J CJ Ciesa Brittney E BE Merrill Madison A MA Hanna James M JM

Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 20180501 5

A mild, redox-neutral, alkylation of imines with potassium alkyltrifluoroborates is described. The reaction proceeds under photoredox conditions at ∼30 °C with primary, secondary, and tertiary alkyltrifluoroborates, leading to alkylation products in moderate to good yield in most cases. Aryl-, vinyl-, and cyclopropyltrifluoroborates failed to react under the reported conditions. ...[more]

PMID: 29722411

Similar Datasets

Visible light-promoted CO2 fixation with imines to synthesize diaryl ?-amino acids.

Project description:Light-mediated transformations with CO2 have recently attracted great attention, with the focus on CO2 incorporation into C-C double and triple bonds, organohalides and amines. Herein is demonstrated visible light -mediated umpolung imine reactivity capable of engaging CO2 to afford ?-amino acid derivatives. By employing benzophenone ketimine derivatives, CO2 fixation by hydrocarboxylation of C=N double bonds is achieved. Good to excellent yields of a broad range of ?,?-disubstituted ?-amino acid derivatives are obtained under mild conditions (rt, atmospheric pressure of CO2, visible light). A procedure that avoids tedious chromatographic purification and uses sustainable sunlight is developed to highlight the simplicity of this method.

| S-EPMC6250672 | biostudies-other

Visible-light promoted regioselective amination and alkylation of remote C(sp<sup>3</sup>)-H bonds.

Project description:The C-N cross coupling reaction has always been a fundamental task in organic synthesis. However, the direct use of N-H group of aryl amines to generate N-centered radicals which would couple with alkyl radicals to construct C-N bonds is still rare. Here we report a visible light-promoted C-N radical cross coupling for regioselective amination of remote C(sp3)-H bonds. Under visible light irradiation, the N-H groups of aryl amines are converted to N-centered radicals, and are then trapped by alkyl radicals, which are generated from Hofmann-Löffler-Freytag (HLF) type 1,5-hydrogen atom transfer (1,5-HAT). With the same strategy, the regioselective C(sp3)-C(sp3) cross coupling is also realized by using alkyl Hantzsch esters (or nitrile) as radical alkylation reagents. Notably, the α-C(sp3)-H of tertiary amines can be directly alkylated to form the C(sp3)-C(sp3) bonds via C(sp3)-H - C(sp3)-H cross coupling through the same photoredox pathway.

| S-EPMC7081228 | biostudies-literature

Visible-Light-Enabled Direct Decarboxylative N-Alkylation.

Project description:The development of efficient and selective C-N bond-forming reactions from abundant feedstock chemicals remains a central theme in organic chemistry owing to the key roles of amines in synthesis, drug discovery, and materials science. Herein, we present a dual catalytic system for the N-alkylation of diverse aromatic carbocyclic and heterocyclic amines directly with carboxylic acids, by-passing their preactivation as redox-active esters. The reaction, which is enabled by visible-light-driven, acridine-catalyzed decarboxylation, provides access to N-alkylated secondary and tertiary anilines and N-heterocycles. Additional examples, including double alkylation, the installation of metabolically robust deuterated methyl groups, and tandem ring formation, further demonstrate the potential of the direct decarboxylative alkylation (DDA) reaction.

| S-EPMC7200280 | biostudies-literature

Visible-Light, Iodine-Promoted Formation of N-Sulfonyl Imines and N-Alkylsulfonamides from Aldehydes and Hypervalent Iodine Reagents.

Project description:Alternative synthetic methodology for the direct installation of sulfonamide functionality is a highly desirable goal within the domain of drug discovery and development. The formation of synthetically valuable N-sulfonyl imines from a range of aldehydes, sulfonamides, and PhI(OAc)? under practical and mild reaction conditions has been developed. According to mechanistic studies described within, the reaction proceeds through an initial step involving a radical initiator (generated either by visible-light or heat) to activate the reacting substrates. The reaction provides a synthetically useful and operationally simple, relatively mild alternative to the traditional formation of N-sulfonyl imines that utilizes stable, widely available reagents.

| S-EPMC6222766 | biostudies-other

Visible Light-Mediated Decarboxylative Alkylation of Pharmaceutically Relevant Heterocycles.

Project description:A net redox-neutral method for the decarboxylative alkylation of heteroarenes using photoredox catalysis is reported. Additionally, this method features the use of simple, commercially available carboxylic acid derivatives as alkylating agents, enabling the facile alkylation of a variety of biologically relevant heterocyclic scaffolds under mild conditions.

| S-EPMC6014829 | biostudies-literature

Visible light induced green transformation of primary amines to imines using a silicate supported anatase photocatalyst.

Project description:Catalytic oxidation of amine to imine is of intense present interest since imines are important intermediates for the synthesis of fine chemicals, pharmaceuticals, and agricultural chemicals. However, considerable efforts have been made to develop efficient methods for the oxidation of secondary amines to imines, while little attention has until recently been given to the oxidation of primary amines, presumably owing to the high reactivity of generated imines of primary amines that are easily dehydrogenated to nitriles. Herein, we report the oxidative coupling of a series of primary benzylic amines into corresponding imines with dioxygen as the benign oxidant over composite catalysts of TiO2 (anatase)-silicate under visible light irradiation of ? > 460 nm. Visible light response of this system is believed to be as a result of high population of defects and contacts between silicate and anatase crystals in the composite and the strong interaction between benzylic amine and the catalyst. It is found that tuning the intensity and wavelength of the light irradiation and the reaction temperature can remarkably enhance the reaction activity. Water can also act as a green medium for the reaction with an excellent selectivity. This report contributes to the use of readily synthesized, environmentally benign, TiO2 based composite photocatalyst and solar energy to realize the transformation of primary amines to imine compounds.

| S-EPMC6272701 | biostudies-literature

Visible Light-Mediated Direct C-H Aroylation and Alkylation of Heteroarenes.

Project description:Herein, we describe the photocatalytic generation of nucleophilic aroyl radicals from simple aroyl chlorides as a universal and efficient cross-coupling strategy for the direct aroylation of heteroarenes. Furthermore, visible light-mediated direct alkylation of heteroarenes has also been achieved using unactivated bromoalkanes as radical precursors. These two strategies feature high functional group tolerance, exclusive regioselectivity for reaction at the more electrophilic position of heteroarenes, easily accessible substrates, and mild reaction conditions. Moreover, mechanism studies of two reactions are carried out to support our hypotheses.

| S-EPMC6714600 | biostudies-literature

Visible light-promoted metal-free sp(3)-C-H fluorination.

Project description:Photoexcited acetophenone can catalyze the fluorination of unactivated C(sp(3))-H groups. While acetophenone, a colorless oil, only has a trace amount of absorption in the visible light region, its photoexcitation can be achieved by irradiation with light generated by a household compact fluorescent lamp (CFL). This operational simple method provides improved substrate scope for the direct incorporation of a fluorine atom into simple organic molecules. CFL-irradiation can also be used to promote certain classic UV-promoted photoreactions of colorless monoarylketones and enones/enals.

| S-EPMC4160356 | biostudies-literature

Visible-Light-Promoted C-S Cross-Coupling via Intermolecular Charge Transfer.

Project description:Disclosed is a mild, scalable, visible-light-promoted cross-coupling reaction between thiols and aryl halides for the construction of C-S bonds in the absence of both transition metal and photoredox catalysts. The scope of aryl halides and thiol partners includes over 60 examples and therefore provides an entry point into various aryl thioether building blocks of pharmaceutical interest. Furthermore, to demonstrate its utility, this C-S coupling protocol was applied in drug synthesis and late-stage modifications of active pharmaceutical ingredients. UV-vis spectroscopy and time-dependent density functional theory calculations suggest that visible-light-promoted intermolecular charge transfer within the thiolate-aryl halide electron donor-acceptor complex permits the reactivity in the absence of catalyst.

| S-EPMC5920654 | biostudies-literature

Orthogonal Syntheses of 3.2.0 Bicycles from Enallenes Promoted by Visible Light.

Project description:Enallenes can be readily converted into two families of 3.2.0 (hetero)bicycles with high diastereoselectivities through the combination of visible light with a suitable Ir(III) complex (1 mol %). Two complementary pathways, namely, a photocycloaddition versus a radical chain, can then take place. Both manifolds grant complete regiocontrol of the allene difunctionalization. This is accompanied by an original 1,3-group shift using sulfonyl allenamides that deliver a congested tetrasubstituted headbridging carbon in the corresponding product.

| S-EPMC8010793 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data